import edu.princeton.cs.algs4.StdOut;
import edu.princeton.cs.algs4.StdRandom;
import edu.princeton.cs.algs4.ThreeSum;

public class Stopwatch {
  private final long start;

  public Stopwatch() {
    start = System.currentTimeMillis();
  }

  public double elapsedTime() {
    long now = System.currentTimeMillis();
    return (now - start) / 1000.0;
  }

  public static void main(String[] args) {
    int N = Integer.parseInt(args[0]);
    int[] a = new int[N];
    for (int i = 0; i < N; i++) {
      a[i] = StdRandom.uniform(-1000000, 1000000);
    }
    Stopwatch timer = new Stopwatch();
    int cnt = ThreeSum.count(a);
    double time = timer.elapsedTime();
    StdOut.println(cnt + " triples " + time + " seconds");
  }
}
